Many ball propelling machines are available. Some, such as McIntosh et al, U.S. Pat. No. 4,323,047; Marty, U.S. Pat. No. 1,211,738; Newgarden, Jr., U.S. Pat. No. 3,878,827; and Kahelin, U.S. Pat. No. 4,423,717; have automated feed devices. All have disadvantages which include tendencies to jam, propensities to release a ball at unforeseen times, or needless cost and complexity.
Especially when a ball propelling machine is used for commercial purposes, it is desirable to provide automated ball feeding means so that upon paying the proper fee, a customer can take batting practice without the need for active attention by batting cage Personnel. To reduce the need for labor even further, some batting cages even automate the fee paying by incorporating coin operated controls. In these batting cages, an amount of time during which balls are pitched at regular intervals or a number of pitches is sold. In any case, it is important that only a single ball is propelled at a time, and that the time of ball propulsion is predictable. Otherwise customers may be hit and injured by an unexpected pitch. It is also important that the ball feed device works reliably in the harsh commercial environment, is economical to manufacture and maintain, is trouble free, and is absolutely safe for both users and cage employees.